Covers for tissue engaging members

Abstract

Moveable tissue engaging members and methods of fabricating and using the same are provided.

1 . A tissue engaging device, comprising:
 a tissue engaging member;   a base member from which the tissue engaging member extends; and   a compressible cover having an attachment end attached to the base member and a distal end opposite the attachment end, wherein the distal end is axially movable along a longitudinal axis of the tissue engaging member to expose the tissue engaging member while the attachment end is stationary.   
     
     
         2 . The tissue engaging device of  claim 1 , wherein the compressible cover has an extended position encasing at least a distal portion of the tissue engaging member, a retracted position exposing at least the distal portion of the tissue engaging member, and a locked position preventing the distal end of the compressible cover from axial movement along the longitudinal axis. 
     
     
         3 . The tissue engaging device of  claim 2 , wherein the compressible cover comprises a hinge element located at a position between the attachment end and the distal end. 
     
     
         4 . The tissue engaging device of  claim 3 , wherein the hinge element bows inward toward the longitudinal axis of the tissue engaging member in the locked position. 
     
     
         5 . The tissue engaging device of  claim 3 , wherein when the hinge element is in the retracted position, the hinge element is flexed outward away from the tissue engaging member. 
     
     
         6 . The tissue engaging device of  claim 1 , wherein the tissue engaging member comprises a blade, a lance or a needle. 
     
     
         7 . The tissue engaging device of  claim 1 , wherein the cover comprises a soft polymer portion which is piercable by the tissue engaging member. 
     
     
         8 . The tissue engaging device of  claim 7 , wherein the soft polymer portion comprises an elastomer. 
     
     
         9 . The tissue engaging device of  claim 8 , wherein the elastomer comprises a thermoplastic elastomer. 
     
     
         10 . The tissue engaging device of  claim 7 , wherein the soft polymer portion bounds at least a distal portion of the tissue engaging member. 
     
     
         11 . The tissue engaging device of  claim 1 , wherein the base member has a planar configuration with distal, proximal and side edges being linear, the side edges at substantially right angles to the distal and proximal edges. 
     
     
         12 . The tissue engaging device of  claim 1 , wherein the cover comprises a first structure extending along the longitudinal axis from one side of the base member and a second structure extending along the longitudinal axis from an opposite side of the base member. 
     
     
         13 . The tissue engaging device of  claim 12 , wherein the each of the first structure and second structure comprise a hinge element configured for being extended, retracted and collapsed. 
     
     
         14 . The tissue engaging device of  claim 12 , wherein when the hinge elements are collapsed in a collapsed position, the cover covers at least a distal portion of the tissue engaging member and the distal end is prevented from moving along the longitudinal axis of the tissue engaging member. 
     
     
         15 . The tissue engaging device of  claim 14 , wherein the hinge elements bow inward toward the longitudinal axis of the tissue engaging member in the collapsed position. 
     
     
         16 . The tissue engaging device of  claim 13 , wherein when the hinge elements are retracted in the retracted position, the hinge elements are flexed outward in opposing directions from the tissue engaging member. 
     
     
         17 . A method of lancing tissue with a tissue engaging device comprising a base member, a tissue engaging member extending from the base member and a compressible cover having an attachment end attached to the base member and a distal end opposite the attachment end, the method comprising:
 moving the distal end of the compressible cover from an extended position in which the distal end encases at least a portion of a tissue engaging member, to a retracted position in which the distal end exposes the tissue engaging member while the attachment end is stationary;   contacting tissue with the exposed tissue engaging member; and   moving the distal end from the retracted position back to the extended position to encase at least a distal portion of the tissue engaging member.   
     
     
         18 . The method of  claim 17 , further comprising:
 locking the cover in a locked position to prevent axial movement of the distal end.   
     
     
         19 . The method of  claim 18 , wherein the compressible cover comprises a hinge element located at a position between the attachment end and the distal end, and wherein locking the cover comprises bowing the hinge element inward toward a longitudinal axis of the tissue engaging member. 
     
     
         20 . The method of  claim 19 , wherein moving the distal end to the retracted position comprises flexing the hinge element outward away from the tissue engaging member.